New Box 3 regime introducing capital-gains and capital-growth tax

Following successive Supreme Court rulings finding the current Box 3 deemed-return regime unlawful, the government committed to a new Box 3 system from 2027. The new regime taxes actual capital growth on savings and actual capital gains on investments annually, replacing the fictitious-return basis used since 2001. Interim measures under the Restoration of Rights Act continue to apply until 2027.